民用涡扇发动机燃油系统健康指标选取

Health Indicators Selection of Civil Turbofan Engine Fuel System

针对民用涡扇发动机燃油系统工作环境恶劣、性能衰退情况频发、表征健康状态的量化指标缺乏的现状,通过机理分析对发动机燃油系统关键部件(燃油计量装置、压差控制器、主燃油泵和增压关断活门)的健康指标选取策略进行了研究。基于已验证的某型民用涡扇发动机燃油系统AMESim模型,注入计量活门内泄漏、电液伺服阀零偏增大、压差活门内泄漏、主燃油泵外泄漏等典型的性能衰退模式进行了性能衰退仿真,并根据燃油系统可测量信息选取了计量活门组件、压差控制器、主燃油泵等作为特定性能衰退模式的健康指标。仿真结果表明:所选取的健康指标对于典型性能衰退模式表现出了良好的监测能力,可作为燃油系统健康状态量化指标评估标准,为燃油系统健康管理和视情维修策略的制定提供参考。

In view of the status of harsh working environment,frequent performance degradation and lack of quantitative indicators to characterize the health status of the civil turbofan engine fuel system,the health indicators selection strategy of the engine fuel system key components(fuel metering unit,differential pressure controller,main fuel pump and shut-off valve)was studied through mechanism analysis. Based on the verified AMESim model of a civil turbofan engine fuel system,the performance degradation simulation was carried out for the typical performance degradation modes such as the internal leakage of fuel metering valve,the increase of the zero offset of the electrohydraulic servo valve,the internal leakage of differential pressure valve and the external leakage of the main fuel pump. According to the measurable information of the fuel system,the metering valve assembly,differential pressure controller and main fuel pump were selected as the health indicators of the specific performance degradation mode. The simulation results showed that the selected health indicators performs well in monitoring typical performance degradation modes,which can be used as the quantitative indicators of the fuel system health state evaluation,and provide a reference for the fuel system health management and the formulation of condition based maintenance strategy.